A flash cube is an obsolete photographic lighting device that contains four small flash bulbs built into a single unit. Each bulb could be used in turn to provide a brief, intense burst of light for taking photographs, typically in low-light situations or indoors.
Flash cubes were popular in the 1960s and 1970s, often used with compact cameras for casual photography. The cube would rotate after each exposure, allowing the next bulb to be used. While they have been largely replaced by modern electronic flashes, flash cubes remain a notable part of photographic history and are sometimes collected by vintage photography enthusiasts.